Hollow concrete building-block.



No. 732,152. PATENTED JUNE 30, 1903. P. S. APPLEMAN & W. MODUFFIE.

HOLLOW CONCRETE BUILDING BLOCK.

APPLICATION FILED FEB. 16, 1903.

no MODEL.

nn H

mmmm

W ITNESSES: ZNVENTORJ p '4 lemm W, Willmnvwjw Aflomey UNITED STATES Patented June 30, 1903.

PATENT OFFICE.

HOLLOW CONCRETE BUILDING-BLOCK.

SPECIFICATION forming part of Letters IPatent No. 732,1 52, dated June 30, 1 903.

Application filed February 16 1903. Serial No. 143,726 (No 'model.)

To all whom, it may concern.-

Be it known that we,FRED S. APPLEMAN and WILLIAM ll/ICDUFFIE, citizens of the United States, residing at Plymouth, county of Marshall, and State of Indiana, have invented certain new and useful Improvements in Hollow Concrete Building-Blocks; and we do hereby declare that the following is a full, clear, and

exact description of the same, reference besuitable register to control the air passing into the room, a block constructed in accordance with our invention having many advantages and the peculiar form of the opening in the block rendering the same particularly adapted for building purposes in constructing the walls of houses, the blocks possessing the necessary strength and durability.

The invention consists in a concrete building-block constructed substantially as shown in the drawings and hereinafter described and claimed.

Figure 1 of the drawings is a perspective View of a hollow concrete building-block constructed in accordance with our invention; Fig. 2, a similar view showing a register connecting therewith; Fig. 3, a transverse vertical section through the block.

In the accompanying drawings, A represents a building-block constructed of concrete and molded into suitable shape, said block being of any desirable size, thickness, and width, as may be found best adapted to the purpose, as we do not wish to be understood as limiting our invention to the size or form of the block, that being left to the manufacturer, and the uses to which it is to be applied governing to a great extent its form and size. In the present instance the block is shown as rectangular in shape and its hollow is formed of double dovetailed-shaped openings B 0,

extending through the center of the block. This hollow in the block differs materially from the hollow building-blocks in ordinary use in that the opening through the block comprises two dovetail openings, each of which join at their narrowest portions at or near the center of the block, forming webs of increasing width and thickness, as shown at 0;, which gives strength to the block where most needed, the sides of the block increasing in thickness as it approaches its center, which is occasioned by the double dovetail opening. This double dovetail opening leaves sufficient material in the side walls of the block to give the required strength and durability to the block in building the walls of houses or other structures, the double dovetail opening being of course in proportion in size to the size of the block. Any of the blocks may have anopening made through its front side, in which may be secured a suitable register, the opening being shown at b and the register at D in Fig.2 of the drawings. This register communicates with a suitable furnace or other heat-generating device, the passage of the heated air into the room being controlled by the register, and the cold air may be taken out of the room and returned to the furnace through the usual means employed for the purpose.

The hollow concrete building-blocks constructed in accordance with our invention may be used in building walls, chimneys, or fines and may be placed together one upon the other, alternating or breaking joints, or in any other manner found necessary in building structures of any character.

Having now fully described our invention, what we claim as new, and desire to secure by Letters Patent, is-

A hollow concrete building-block having a double dovetail-shaped opening through it, that portion of each dovetail opening decreasing in width joining at or near the center of the block whereby the side walls of the block gradually increase in thickness to give strength and durability thereto, substantially as and for the purpose set forth.

FRED S. APPLEMAN. WILLIAM MCDUFFIE. Witnesses:

GEORGE H. KRUGER, CHARLES E. GROUP. 

